China: Study on Weight-Lowering Drugs

Phentermine-topiramate and GLP-1 receptor agonists seemed to be the best drugs for reducing weight in adults with overweight and obesity, suggests a recent study. Further, semaglutide was found to be most effective amongst the GLP-1 agonists.

When lifestyle modifications fail in adults with overweight and obesity, pharmacotherapy provides an option. Qingyang Shi, Sichuan University, Chengdu, China, and colleagues summarised the latest evidence for the benefits and harms of weight-lowering drugs in a systematic review and network meta-analysis.

The researchers searched the online databases from inception to March 23, 2021, for randomized controlled trials of weight-lowering drugs in adults with overweight and obesity. The evidence was summarized and Grading of Recommendations Assessment, Development, and Evaluation frameworks were applied to rate the certainty of the evidence, calculate the absolute effects, categorize interventions, and present the findings.

The search identified 14,605 citations, of which 143 eligible trials enrolled 49,810 participants.

Key Findings

• Except for levocarnitine, all drugs lowered bodyweight compared with lifestyle modification alone; all subsequent numbers refer to comparisons with lifestyle modification.
• High to moderate certainty evidence established phentermine–topiramate as the most effective in lowering weight (odds ratio [OR] of ≥5% weight reduction 8.02; mean difference [MD] of percentage bodyweight change −7.97) followed by GLP-1 receptor agonists (OR 6.33; MD −5.76).
• Naltrexone–bupropion (OR 2.69), phentermine–topiramate (2.40), GLP-1 receptor agonists (2.17), and orlistat (1.72) were associated with increased adverse events leading to drug discontinuation.
• In a post-hoc analysis, semaglutide, a GLP-1 receptor agonist, showed substantially larger benefits than other drugs with a similar risk of adverse events as other drugs for both likelihoods of weight loss of 5% or more (OR 9.82) and percentage body weight change (MD −11.41).

The authors concluded, "phentermine–topiramate and GLP-1 receptor agonists in adults with overweight and obesity, proved the best drugs in reducing weight; of the GLP-1 agonists, semaglutide might be the most effective."

Reference

The study titled, "Pharmacotherapy for adults with overweight and obesity: a systematic review and network meta-analysis of randomised controlled trials," was published in The Lancet.

DOI: https://doi.org/10.1016/S0140-6736(21)01640-8